1. Field of the Invention
The present invention relates to a touch-type pointing device with wireless input capability and, more particularly, to a touch-type pointing device having a sensing pen which is able to execute and confirm the operation of inputting coordinate point in wireless manner.
2. Description of Related Art
The touch pad is a well-known computer input device for providing functions similar to those of the mouse and track ball. As shown in FIG. 5, the touch pad 70 has a transparent electrode 71 and a plurality of buttons 72xcx9c74 for connecting to the control circuit (not shown) therein. The output of the control circuit is connected to the input port of a computer via conductive wires.
In use of the touch pad, a sensing pen 80 is provided to touch a coordinate point on the transparent electrode 71, so as to select a corresponding coordinate point on the computer screen. After the desired coordinate point is selected, the buttons 72xcx9c74 of the touch pad 70 are pressed to confirm and execute the input operation.
The above input operation is not convenient because the user must use both of his/her hands to hold the sensing pen 80 and press the buttons 72xcx9c74 of the touch pad 70 at the same time. Furthermore, the touch pad 70 is generally as small as a palm for the user to hold by one hand, and thus, it is not easy to have one hand hold the sensing pen 80 and the other hand press the buttons 72xcx9c74 while holding the touch pad 70. Therefore, there is a desired to have a novel touch-type pointing device to mitigate and/or obviate the aforementioned problems.
The object of the present invention is to provide a touch-type pointing device with wireless input capability for being conveniently operated by the user.
To achieve the object, the touch-type pointing device in accordance with the present invention includes a touch unit and a sensing pen. The touch unit has a transparent electrode and a control circuit connected to the transparent electrode for detecting a variance of impedance in the transparent electrode to have a signal representing a coordinate point, and transmitting and receiving signals. The sensing pen has a plurality of switches, each being closed to form a LC loop for transmitting signals in response to the signals from the touch unit.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.